the bug will cause CJK chars in filename been stripped out.

for example:

`/media/mydisk/fooにほん.rar`  will result in `/media/mydisk/foo` so the open will fail

due to

```cpp
    std::string AnsiArcName;
    if (r->ArcName!=nullptr)
    {
      AnsiArcName=r->ArcName;
      if (!AreFileApisANSI())
        IntToExt(r->ArcName,AnsiArcName);
    }

    std::wstring ArcName;
    if (r->ArcNameW!=nullptr && *r->ArcNameW!=0)
      ArcName=r->ArcNameW;
    else
      CharToWide(AnsiArcName,ArcName);

    Data->Cmd.AddArcName(ArcName);
    Data->Cmd.Overwrite=OVERWRITE_ALL;
    Data->Cmd.VersionControl=1;

    Data->Cmd.Callback=r->Callback;
    Data->Cmd.UserData=r->UserData;

    // Open shared mode is added by request of dll users, who need to
    // browse and unpack archives while downloading.
    Data->Cmd.OpenShared = true;
    if (!Data->Arc.Open(ArcName,FMF_OPENSHARED))
    {
      r->OpenResult=ERAR_EOPEN;
      delete Data;
      return NULL;
    }
```

in `Data->Arc.Open` it will do `WideToChar` which cause the CJK bytes got lost.

but if it calls `CharToWide` first (when `ArcNameW` is nullptr), when it do the reverse, it get the right filename back.